161205106215017 has 4 divisors (see below), whose sum is σ = 161205253129860. Its totient is φ = 161204959300176.

The previous prime is 161205106214923. The next prime is 161205106215019. The reversal of 161205106215017 is 710512601502161.

161205106215017 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 28041907202521 + 133163199012496 = 5295461^2 + 11539636^2 .

It is a cyclic number.

It is not a de Polignac number, because 161205106215017 - 2¹⁶ = 161205106149481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161205106215019) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71799038 + ... + 74010215.

It is an arithmetic number, because the mean of its divisors is an integer number (40301313282465).

Almost surely, 2^{161205106215017} is an apocalyptic number.

It is an amenable number.

161205106215017 is a deficient number, since it is larger than the sum of its proper divisors (146914843).

161205106215017 is a wasteful number, since it uses less digits than its factorization.

161205106215017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146914842.

The product of its (nonzero) digits is 25200, while the sum is 38.

Adding to 161205106215017 its reverse (710512601502161), we get a palindrome (871717707717178).

The spelling of 161205106215017 in words is "one hundred sixty-one trillion, two hundred five billion, one hundred six million, two hundred fifteen thousand, seventeen".